JP4046854B2 - Method for manufacturing printed wiring board with pins - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a printed wiring board with a PGA type pin that can be used for a semiconductor package, a multi-chip module, and the like.
[0002]
[Prior art]
Conventionally, organic printed wiring boards using a glass epoxy substrate or the like have connected between conductor layers by through holes, so the so-called PGA (Pin Grid Array) type in which pins are provided using these through holes is the mainstream. there were.
[0003]
Since the wiring board with pins using this through-hole insertion type pin is mounted using a dedicated connector, it can be mounted reliably, and if the component to be mounted on the wiring board fails or There is an advantage that the work for replacing parts becomes easy when upgrading. However, there is a problem that a space for providing a through hole for inserting a pin into the wiring board is required, and it is difficult to increase the density and size.
[0004]
In order to solve the problem of the through hole insertion type pinned wiring board, which is difficult to achieve high density and miniaturization, an interstitial via hole (IVH) structure is used as an interlayer connection method that does not use through holes. It has been developed. In this IVH structure, a mounting system using a BGA (Ball Grid Array) type is adopted because there is no through hole and the mounting area can be further reduced.
[0005]
[Problems to be solved by the invention]
However, BGA type wiring boards with pins using such a wiring board of IVH structure require advanced mounting technology when connecting the ball and the mother board, and confirming the connection state between the ball and the mother board. However, it has a problem that it is not versatile, and that it is difficult to replace parts at the time of upgrade.
[0006]
The present invention is a method for manufacturing a highly versatile PGA type printed wiring board with a pin that can be very easily connected to a mother board or the like and check the connection state and can be easily replaced at the time of an upgrade. Is intended to be provided at low cost.
[0007]
[Means for Solving the Problems]
For this purpose, a manufacturing method of a printed wiring board with pins according to claim 1 of the present invention firstly connects external pads to pads formed on a bonding surface of a heat-resistant glass epoxy substrate used as a PGA type printed wiring board. Soldering metal pins for terminals, and then stepped so that the joint surface side of the heat-resistant glass epoxy substrate and the metal pins for external connection terminals are widened correspondingly. An adhesive is applied to at least one surface of the reinforcing plate in which the through-hole is formed, and then the reinforcing plate is made of the heat-resistant glass epoxy substrate while passing the metal pin through the through-hole. The reinforcing plate is bonded to the bonding surface of the heat-resistant glass epoxy substrate and the through hole is filled with the adhesive.
[0008]
To achieve the above object, a method for manufacturing a printed wiring board with pins according to claim 2 of the present invention first comprises a PGA type printed circuit board in which pads for soldering metal pins for external connection terminals are provided on the joint surface. Reinforcement in which a heat-resistant glass epoxy substrate used as a wiring board is prepared, and then a through-hole formed by stepping so that the joint surface side becomes wider corresponding to each metal pin for an external connection terminal Solder is present at the portion of the plate that becomes the joint between the metal pin and the pad inserted into the through hole, and then the joint surface of the heat-resistant glass epoxy substrate and the through hole of the reinforcing plate Adhesive is applied to at least one of the formed surfaces, and then the surface of the reinforcing plate on which the through-hole is formed is brought into contact with the bonding surface of the heat-resistant glass epoxy substrate so that the reinforcing plate is moved forward. Bonding to the bonding surface of the heat-resistant glass epoxy substrate, and then soldering the metal pin and the pad by melting the solder existing in the portion to be the bonding portion of the metal pin and the pad .
[0009]
The printed wiring board with pins manufactured by the method for manufacturing a printed wiring board with pins according to claim 1 of the present invention performs connection of the mother board and the like, confirmation of the connection state, and parts replacement work at the time of upgrade, etc. very easily. Therefore, the printed wiring board with high versatility can be provided at low cost because it has a simple structure employing the PGA type.
[0010]
The printed wiring board with pins manufactured by the method for manufacturing a printed wiring board with pins according to claim 2 of the present invention performs connection of the mother board and the like, confirmation of the connection state, and parts replacement work at the time of upgrade, etc. very easily. Therefore, the printed wiring board with high versatility can be provided at low cost because it has a simple structure employing the PGA type.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a printed wiring board with pins according to a first embodiment of the present invention. In the figure, reference numeral 1 denotes a printed wiring board, and this printed wiring board 1 is used with LSI, chip parts, etc. mounted on the upper surface thereof.
[0014]
As the printed wiring board 1, an organic multilayer printed wiring board having an IVH structure in which no through hole is formed is used. Examples of the organic multilayer printed wiring board having the IVH structure include a built-up multilayer wiring board, a single-sided circuit board lamination type multilayer wiring board (filed by the applicant of the present application), and a B ² it type new high-density printed wiring board ( International Packaging Society Vol.11 No.7 NOV.1996 Refer to P475-478), All-layer IVH New Resin Multilayer Wiring Board (See International Packaging Society Vol.11 No.7 NOV.1996 P485-486) Any of the above can be used.
[0015]
In the present embodiment, a built-up multilayer wiring board is used as the printed wiring board 1, and the printed wiring board 1 is laminated, for example, in a six-layer structure by batch pressing. For example, the printed wiring board 1 has an area of 35 × 35 mm and a thickness of 0.4 to 0.6 mm.
[0016]
The multilayer wiring board having a built-up structure used as the printed wiring board 1 includes a glass cloth base epoxy resin substrate (hereinafter referred to as a glass epoxy substrate), a glass cloth base BT (bismaleimide-triazine) resin substrate, and the like. Can be used. The material of the printed wiring board 1 is preferably the same as that of a reinforcing plate described later in order to avoid a difference in thermal expansion. In the present embodiment, a heat-resistant glass epoxy substrate is used as the printed wiring board 1.
[0017]
A large number of pads 2 for soldering metal pins for external connection terminals are formed on the lower surface of the printed wiring board 1, and the metal pins 3 for external connection terminals are soldered to the pads 2, respectively. It is joined by. In this case, the lower surface of the printed wiring board 1 becomes the joint surface 1 a of the metal pin 3. As the pad 2, a conductive metal such as copper that can constitute an electrical contact is used. As the metal pin 3, for example, a nail head pin is used. For the soldering, eutectic solder, high-temperature solder or the like is used.
[0018]
Further, a reinforcing plate 5 in which a plurality of through holes 4 corresponding to the metal pins 3 are formed is bonded to the bonding surface 1a of the metal pins 3 of the printed wiring board 1 by an adhesive 7. The lower surface of the reinforcing plate 5 also serves as a joint surface 1a of the reinforcing plate 5. The through hole 4 is stepped so that the side of the joint surface 1a is widened, and this stepped processing is performed by, for example, a double drill or laser processing. The adhesive 7 is preferably made of an organic adhesive. Examples of the organic adhesive include epoxy resin, polyimide resin, thermosetting polyphenolene ether (PPE), epoxy resin, and thermoplastic resin. It is desirable that the resin be at least one resin selected from a composite resin of the above, a composite resin of an epoxy resin and a silicone resin, and a BT resin.
[0019]
As the reinforcing plate 5, a plate made of a resin material can be used. As described above, a laminate made of heat-resistant glass epoxy, which is the same material as the printed wiring board 1, is used to avoid a difference in thermal expansion. A plate is preferred. Note that both the printed wiring board 1 and the reinforcing plate 5 may be FR-5 laminates. Further, the reinforcing plate 5 has an area equal to or smaller than that of the printed wiring board 1 and a thickness of 0.8 mm. In addition, as shown in FIG. 1, the length of the said metal pin 3 shall be determined so that the said metal pin 3 may protrude from the reinforcement board 5 only predetermined length in the state which joined the reinforcement board 5. As shown in FIG. .
[0020]
The printed wiring board with pins of the present embodiment is configured as shown in FIG. 1, and there are two methods for manufacturing the printed wiring board with pins as described below.
[0021]
FIG. 2 is a view for explaining a first manufacturing method of a printed wiring board with pins of the present embodiment, and the same parts as those in FIG.
In the first manufacturing method, first, metal pins 3 for external connection terminals are joined to the pads 2 formed on the lower surface 1a of the printed wiring board 1 by soldering. Next, an adhesive is applied to at least one of the lower surface 1 a of the printed wiring board 1 and the upper surface of the reinforcing plate 5. An adhesive sheet or a prepreg may be used instead of applying the adhesive.
[0022]
Next, the reinforcing plate 5 in which the through holes 4 are formed corresponding to the individual metal pins 3 for the external connection terminals is lifted from below the metal pins 3 as shown by the arrows in FIG. The lower surface 1a of the printed wiring board 1 and the upper surface of the reinforcing plate 5 are brought into contact with each other. As a result, the reinforcing plate 5 is bonded to the joint surface 1a of the printed wiring board 1, and the adhesive is filled into the through holes, resulting in the state shown in FIG.
[0023]
FIG. 3 is a view for explaining a second manufacturing method of the printed wiring board with pins according to the present embodiment. The same parts as those in FIG.
In the second manufacturing method, first, the printed wiring board 1 provided with the pads 2 for soldering the metal pins 3 for external connection terminals is left without the metal pins 3 being soldered. In the reinforcing plate 5 in which the through holes 4 are formed corresponding to the metal pins 3 for the external connection terminals, the solder 8 is present in the portion that becomes the joint between the metal pins 3 and the pads 2 (that is, the upper surface of the metal pins 3). Leave it in a state. Next, an adhesive is applied to at least one of the lower surface 1 a of the printed wiring board 1 and the upper surface of the reinforcing plate 5. An adhesive sheet or a prepreg may be used instead of applying the adhesive.
[0024]
Next, the reinforcing plate 5 is lifted from below as indicated by the arrow in the drawing, and the lower surface 1a of the printed wiring board 1 and the upper surface of the reinforcing plate 5 are brought into contact with each other. As a result, the reinforcing plate 5 is bonded to the joint surface 1 a of the printed wiring board 1. Thereafter, the solder 8 of the joint is melted and the metal pins 3 and the pads 2 are soldered. Thereby, the metal pin 3 is soldered to the joint surface 1a of the printed wiring board 1, and the state shown in FIG. 1 is obtained.
[0025]
The printed wiring board with pins of the present embodiment manufactured by the first or second manufacturing method described above can perform connection replacement with a mother board or the like, confirmation of the connection state, and parts replacement work at the time of upgrade or the like. Since it becomes a printed wiring board with a highly versatile pin and has a simple structure employing the PGA type, it can be provided at low cost.
[0026]
In the above embodiment, the through hole 4 of the reinforcing plate 5 has a stepped shape. Instead, as shown in FIG. 4, a through hole 6 without a step is used to further reduce the cost. Good. In this case, a step corresponding to the thickness of the head of the metal pin 3 occurs when the reinforcing plate 5 is bonded to the joint surface 1 a of the printed wiring board 1, but the step is filled with the adhesive 7. Therefore, it is substantially the same as the state shown in FIG.
[0027]
【The invention's effect】
As described above, according to the present invention, a highly versatile PGA type pin that can be very easily connected to a mother board or the like and can be checked for connection status, and can be easily replaced during upgrades. A method for manufacturing a printed wiring board with a cover can be provided at a low cost.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a printed wiring board with pins according to a first embodiment of the present invention.
FIG. 2 is a drawing for explaining a first manufacturing method of the printed wiring board with pins of the first embodiment.
FIG. 3 is a drawing for explaining a second manufacturing method of the printed wiring board with pins of the first embodiment.
FIG. 4 is a view showing a modification of the through hole of the reinforcing plate of the first embodiment.
[Explanation of symbols]
1 Printed wiring board 1a Bottom surface (joint surface)
2 Pad 3 Metal pins 4 and 6 Through hole 5 Reinforcement plate 7 Adhesive 8 Solder

Claims (2)

First, solder a metal pin for an external connection terminal to a pad formed on a bonding surface of a heat resistant glass epoxy substrate used as a PGA type printed wiring board, and then, the bonding surface of the heat resistant glass epoxy substrate and Adhesive agent on at least one of the surfaces of the reinforcing plate in which the through hole is formed so that the joint surface side is widened corresponding to the metal pin for each external connection terminal. Then, the reinforcing plate is brought into contact with the joining surface of the heat-resistant glass epoxy substrate while the metal pin is passed through the through hole, and the reinforcing plate is brought into contact with the joining surface of the heat-resistant glass epoxy substrate. A method for manufacturing a printed wiring board with pins, wherein the adhesive is also filled in the through-holes. First, a heat-resistant glass epoxy substrate used as a PGA type printed wiring board provided with pads for soldering metal pins for external connection terminals on the joint surface, and then for each external connection terminal Solder to a portion of the reinforcing plate in which a through hole formed by stepping so as to widen the joint surface corresponding to the metal pin is a joint between the metal pin and the pad inserted into the through hole. Next, an adhesive is applied to at least one of the bonding surface of the heat-resistant glass epoxy substrate and the surface of the reinforcing plate where the through hole is formed, and then the penetration of the reinforcing plate The surface in which the hole is formed is brought into contact with the bonding surface of the heat-resistant glass epoxy substrate, and the reinforcing plate is adhered to the bonding surface of the heat-resistant glass epoxy substrate, and then the metal pin and the front Method for producing a pin with a printed wiring board, wherein a solder is present in the portion serving as the joining portion of the pad is melted soldering the metal pins and the pads.

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